Museum of Freemasonry - Masonic Library
Brethren in some respects it is a pity that we live in close proximity to a major city as it virtually denies us the opportunity afforded to millions of men over the millennia, that is of laying out in a field at night, looking up at the band of encircling stars in all their glory. The excess light and pollution dim most of the stars from our view.

Those stars have inspired and puzzled men and led to much speculation as to the nature of things and, of course, their creation.

Observant men noticed and classified a small group as wanderers, because of their relative, but slow, movement against the stable background of stars. These wanderers were later identified as the nearer planets.

Over the last four decades many more new wanderers have been noticed in the heavens, and catalogued, but these were travelling at quite perceptible rates, easily noticed by the naked eye. They are of course, the many satellites launched by man in his exploration of inner space, that space in close proximity to Earth, just above the encircling envelope of atmosphere.

Throughout all time, man has been puzzled and inspired and also speculated as to the true nature of the spectacular streaks of light that from time to time flashed across the night skies. They have been called shooting stars, falling stars, and later, meteors. Thus our story begins.

Meteors were a complete mystery to mankind for thousands of years and were generally considered to be purely atmospheric phenomena.

The word meteor derived from the Greek meaning something aloft or up above, with its obvious kinship to ‘meteorology’ is a survival of this old belief.

The visible meteor trails we see, are caused by fragments of matter from space entering the Earth’s orbit at enormous velocities. The friction caused by these particles with the atmosphere causes most of the matter to be superheated and rapidly vaporised and it is the incandescent vapour that is mostly seen, as the meteor trail.

Scientists of the French Academy in the closing years of the 18th century dismissed all tales of stones falling from the sky as superstitious nonsense. Then in 1803 a great shower of meteoric stones fell on Normandy. Thereafter no one doubted the fact that objects entered the atmosphere from space and occasionally reached the surface.

In 1833 a great shower of objects fell on Southern Carolina and dramatically demonstrated that meteors could occur not only as sporadic wanderers, but also in enormous clusters or streams. Continual observations revealed that there are large numbers of those meteor showers. For example around the 12th August of each year meteors will be seen streaking (apparently), from the heart of the constellation Perseus, at the rate of one per minute.

Actually it’s the Earth passing through the same cloud of dust and debris in its orbit around the sun. There is a similar occurrence around 14th November involving the constellation Leo. It is probable that the debris clouds through which the Earth passes belonged to comets that had finally disintegrated under the Sun’s solar radiation.

The Italian astronomer Schiaparelli proved that the Perseid’ meteors which appear in August move in the same orbit as comet 1862 III. Similarly the Leonid meteors in November were found to follow the same orbit as Comet 1866 I.

Almost all observations of “shooting stars” were made by naked eye with no equipment but a notebook, watch and a thorough knowledge of the constellations. Thousands of such naked eye observations built up all the knowledge on meteors until radio waves were linked to meteors, and then, later, the advent of radar helped.

Meteors leave electrons behind as they burn up in the Earth’s atmosphere. These electrons can reflect radio waves. During a meteor shower, a radio receiver can sometimes receive signals from radio stations or other radio sources, up to 2,000 kilometres away, which they would not normally do.

Radar is a tool of such tremendous power that operates night and day and in all kinds of weather, and so it became an indispensable tool for tracking meteors. Meteors do occur in daylight but have to be exceptional, to be seen.

The British radar designed to pick up German bombers in World War 2, picked up strange echoes 70 to 80 miles above the Earth. These echoes proved not to be meteors (which are generally too small to be detected), but the trails of intensely heated gas left behind.

Some remarkable discoveries were very quickly made. A group of radio astronomers at Manchester discovered great meteor showers occurring during every day. Between June and August vast belts of meteors are sweeping unseen and hitherto unsuspected across the daylight skies of Earth.

Automated equipment now maintains a continuous watch over the sky and when a meteor is detected its trail is plotted along with its height and velocity. From this data its previous orbit through space is computed.

Astronomers had been arguing that a substantial portion off all meteoric matter did not belong to the Solar System but came from interstellar space. The evidence was compelling because some meteors appeared to be travelling far too fast to remain in the Solar System.

In the Earth’s neighbourhood any object moving at more than 94,000 MPH could only be a visitor to the Solar System and not a permanent resident.

The more accurate radar methods proved conclusively that meteors travelling faster than this solar speed-limit, did not exist. All are captives of the Sun as are Earth and the other planets, and revolve around it in similar closed orbits.

Although meteors do not travel faster than 94,000 MPH with respect to the Sun, the velocities with which they meet our atmosphere head-on, can be as high as 160,000 MPH as Earth is racing along its own orbit at 66,000 MPH. On the other hand when a meteor catches up to the Earth from the rear, its speed of approach is relatively slow and this sometimes produces a remarkable effect. Most meteor trails flash out and vanish in a second or so. When a meteor enters the Earth’s atmosphere from the rear, it may make a sedate and relatively slow streak across the sky at 28,000 MPH.

With meteors, the disparity between the size of the object and its trail is extreme. A very bright meteor producing a burst of light that outshines all the stars put together is only about one half-inch in diameter. Such a giant is rare, perhaps as few as 1,000 hit the atmosphere hourly, but are spread thinly over the entire surface area of the Earth.

The Earth is a rather large satellite of the Sun with a diameter of 8,000 miles, and carves out a tunnel 66,000 miles long in an hour as it moves along its orbit. The total number of meteors hitting the atmosphere every hour is enormous, probably in the billions, but the vast majority are smaller than grains of sand.

In space travel you would probably die of old age before meeting a meteor large enough to do any serious damage. However, dust in space would sand blast viewing windows and optical surfaces after a few years of continuous operations and render them useless.

About ten times per day Earth encounters objects large enough not to be consumed by friction and to reach the surface intact. They are then called meteorites and are of great interest to scientists, as samples of extra-terrestrial matter.

On inspection these meteorites turn out to be made of stone or nickel/iron and look as if they came from a slag-heap, although nowadays it is possible for a man-made artefact to fall from a decaying orbit, as space junk. Remember the Spacelab.

Once or twice a century really large meteorites hit the Earth. It happened in Russia in 1908 and again in 1947. On 30th June, 1908 a terrifying explosion occurred in Siberia near the Stony Tunguska River. It generated a dazzling fireball and shock waves reminiscent of a thermonuclear blast. In an instant, 60,000 trees lay flattened and charred. No one knows for sure what caused the event, but astronomers think it was probably part of a comet nucleus impacting the atmosphere at high speed and exploding 6 kilometres above the ground. On 12th February, 1947 the second great meteorite of the twentieth century detonated less than 400 kilometres from Vladivostok, and is actually believed to have been the head of a small comet as it left no solid residue or even an impact crater. What it did leave was another forest blasted flat by the explosion rivalling that of the newly invented uranium bomb.

During the history of the Earth there must have been thousands of such collisions but the effects of weather and vegetation have obliterated much of the evidence. Most would have landed in the sea because of its greater surface area than the land.

Until recently the famous meteor crater in Arizona with a diameter of over 4,000 feet, was the largest known. Then during the second World War, American and Canadian pilots noticed a curious circular lake in Northern Quebec and this was subsequently named the Ungava Crater with a diameter of more than 11,000 feet.

Photography from space has revealed one very large astrobleme (literally – star wound), which has been named The Vredefort Structure in South Africa, having a diameter of over thirty miles.

In Australia Wolf Creek crater in WA has a diameter of 2,800 feet; Henbury is 650 feet; Boxhole 570 feet; Dalgaranga 230 feet. Ours are small by comparison.

Gosses Bluff in the N.T. is a very ancient impact structure that is much eroded.

During October of the year 2008, the Sun Herald had an article mentioning a meteorite that landed in central Australia near Henbury and, at this moment the impact site has not yet been discovered. The article also elaborated on the Henbury Meteor that struck approximately 4,700 years ago. That giant meteor was travelling at more than 25,000 miles an hour when it disintegrated and hit Earth creating twelve giant craters 145 kilometres S.W. of Alice Springs.

You only see the glowing trail of the meteor in the sky, for a few seconds if that, and it is only in those few seconds that fusion or surface melting takes place. The change in energy from speed to heat is so great and the speed so reduced that fusion quickly ceases as the air resistance can no longer produce enough heat to continue the fusion on the surface unless it is exceptionally large and the mass is too great to be slowed by air resistance. When surface fusion ceases the meteor ceases to glow and becomes invisible. Despite the great surface heat generated, enough to melt iron, the centre of a meteorite that reaches the surface of the earth is still deeply frozen from the extreme cold of space and, invariably within a few minutes of landing, is covered in frost

In 1928 a small stony meteorite fell at night in a backyard at Narellan and was heard to hit by a father and his children who searched for and found it. The interesting thing is that 10 to 15 minutes earlier they had been watching the flash of the meteor through the sky until it had ceased to glow and it had taken that length of time to fall the remaining 40 to 50 miles to earth

The elements known to us on earth are represented in meteorites so nothing new or unknown has reached us from space. However, the crystallization pattern in the iron/nickel meteorites reveals their extra-terrestrial origin. Sometimes the meteorite contains chlorides of iron that are stable in space but not on the earth. The chloride quickly changes to hydrochloric acid that causes rapid disintegration of the meteorite unless it can be rapidly transferred to a container having an inert atmosphere such as nitrogen.

Investigation into the ages of meteorites utilising different techniques has revealed a range of ages from the very young (12,500 years old) to the very old (2.9 billion years), and this latter figure is twice the age of the oldest pre-cambrian rocks on earth.

It is to be hoped that a large meteorite never falls on a city for the damage could be catastrophic, and for the further reason, that if it landed during a period of international tension, could be misinterpreted and initiate a war. Defence systems have to differentiate between a plunging meteor and an incoming ballistic missile.

In February 1994, U.S. President Bill Clinton was woken by his staff with news of a possible military attack on America detected by six orbiting satellites. It soon became clear that what the satellites had picked up was not incoming enemy missiles but a massive meteor that ultimately exploded high in the atmosphere. In May 1996, another gigantic meteor with a diameter of more than 300 metres, skimmed by the Earth just three days after it was first detected by military satellites. It’s still out there, somewhere.

There is considerable evidence that without meteors we would have had no long-range radio communications. The only way radio waves can get around the curve of the Earth was by bouncing off the ionised layers in the upper atmosphere some seventy miles above our head. The advent of communication satellites changed the reliance on direct radio. It is also believed that the gentle rain of meteoric dust from space is responsible for at least one of the electrified layers in our stratosphere.

Some research in Australia proved that meteors are linked with meteorology because the falling dust seeds clouds and causes rain. Long-range weather forecasts therefore may need to allow for meteor streams that the Earth will encounter in its passage through space. These are now predictable but not avoidable.

All meteors and meteorites add over two million tons of matter to the Earth each year. If this has been going on since the formation of the Earth, a layer approximately ten feet thick has been deposited over the whole surface of the planet. It means that much of what the farmer ploughs today, is ancient star-dust, milled and mixed for the millennia by the wind and rain.

One of the giant planets may deflect a meteor stream half a billion miles from Earth, so that ages later, our world encounters an abnormally high concentration of dust as it sweeps along its orbit. So an event in far off space and time can cause rains and floods that may destroy many lives and undo the work of generations of men.

The largest meteorite recovered intact to date is the 60-ton monster at Hoba West in South Africa. The second largest surviving meteorite is the Ahnightito weighing 31 tons which was discovered along with two smaller ones, in Greenland by the American Robert Peary in 1894. It is interesting to note that it is composed chiefly of iron and that the three masses had long been used by the Inuit as a source of metal for the manufacture of knives and other metallic implements. Our largest meteorite weighs twelve tons, at Munderabilla in WA. I do not know if it is available or accessible for inspection. Previously, pride of place was taken by the Cranbourne (near Melbourne) meteorite, which weighs three and a half tons and is on display in the British Museum.

The extreme heat generated by an impact can create new mineral specimens such as Tektites, which are small dark and look like glassy buttons and are found in several areas around the World.

Some meteors found in Antarctica came from the Moon and/or Mars and are presumed to have been blasted from the surface of those satellites by the explosive impact of asteroids, the fragments being ultimately swept up by the Earth in its orbit around the Sun. I suppose it begs the question as to whether any portion of Earth has been blasted into space by a large impact, and has, in turn, been swept up by the Moon or another planet. Possibly not, because of our much greater gravitational attraction, but it is interesting to speculate on the possibility of it having happened.

Worshipful Master and brethren, we should appreciate the wonder of the celestial works of the G.A.O.T.U. The few facts and figures covered here in this tiny aspect of the mighty topic of Astronomy should whet our appetite for learning and appreciating more. The greatest thinkers of all ages have been trying to understand the cosmos and there is much more for them and for us, to learn.

Finally, whilst on a recent holiday I visited the museum in Wingham and saw a meteorite of approx 20 kilos that landed in a ploughed field nearby in 1886 but all I could do was look and not touch, what a shame.

VW Bro Robert Taylor